1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include <__config>
10#include <chrono>
11#include <filesystem>
12#include <time.h>
13
14#if defined(_LIBCPP_WIN32API)
15# include "time_utils.h"
16#endif
17
18#if defined(_LIBCPP_WIN32API)
19# define WIN32_LEAN_AND_MEAN
20# define NOMINMAX
21# include <windows.h>
22#endif
23
24#if __has_include(<unistd.h>)
25# include <unistd.h> // _POSIX_TIMERS
26#endif
27
28#if __has_include(<sys/time.h>)
29# include <sys/time.h> // for gettimeofday and timeval
30#endif
31
32#if defined(__APPLE__) || defined(__gnu_hurd__) || (defined(_POSIX_TIMERS) && _POSIX_TIMERS > 0)
33# define _LIBCPP_HAS_CLOCK_GETTIME
34#endif
35
36_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
37
38const bool _FilesystemClock::is_steady;
39
40_FilesystemClock::time_point _FilesystemClock::now() noexcept {
41 typedef chrono::duration<rep> __secs;
42#if defined(_LIBCPP_WIN32API)
43 typedef chrono::duration<rep, nano> __nsecs;
44 FILETIME time;
45 GetSystemTimeAsFileTime(&time);
46 detail::TimeSpec tp = detail::filetime_to_timespec(time);
47 return time_point(__secs(tp.tv_sec) + chrono::duration_cast<duration>(__nsecs(tp.tv_nsec)));
48#elif defined(_LIBCPP_HAS_CLOCK_GETTIME)
49 typedef chrono::duration<rep, nano> __nsecs;
50 struct timespec tp;
51 if (0 != clock_gettime(CLOCK_REALTIME, &tp))
52 __throw_system_error(errno, "clock_gettime(CLOCK_REALTIME) failed");
53 return time_point(__secs(tp.tv_sec) + chrono::duration_cast<duration>(__nsecs(tp.tv_nsec)));
54#else
55 typedef chrono::duration<rep, micro> __microsecs;
56 timeval tv;
57 gettimeofday(&tv, 0);
58 return time_point(__secs(tv.tv_sec) + __microsecs(tv.tv_usec));
59#endif
60}
61
62_LIBCPP_END_NAMESPACE_FILESYSTEM
63

source code of libcxx/src/filesystem/filesystem_clock.cpp